000
AXPZ20 KNHC 120339
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 
0405 UTC WED APR 12 2006

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY 
THROUGH 0315 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 8N83W 4N92W 4N102W 6N110W 7N126W
3N140W. SCATTERED STRONG CONVECTION IS WITHIN 60 NM EITHER SIDE 
OF THE ITCZ BETWEEN 108W-110W. SCATTERED MODERATE CONVECTION 
IS WITHIN 60 NM EITHER SIDE OF THE AXIS BETWEEN 93W-97W.

...DISCUSSION...
THE NE PAC IS DOMINATED BY A LONGWAVE TROUGH WITH A DEEP LAYERED 
CYCLONE NEAR 38N132W WITH A MEAN TROUGH AXIS S TO NEAR 15N135W. 
ONE EMBEDDED SHORTWAVE HAS MOVED INLAND THE CONUS ALONG 36N122W 
30N109W. A SECOND SHORTWAVE ENTERS THE DISCUSSION AREA ALONG 
32N130W 18N131W. A BAND OF DRY AIR IS NOTED WITHIN 60 NM EITHER 
SIDE OF LINE 32N108W 24N119W THEN COVERING THE DISCUSSION 
AREA FROM 16N TO 26N W OF 122W.

AN UPPER ANTICYCLONE IS ESTIMATED NEAR 7N118W AND ANOTHER NEAR 
16N107W. A COMBINED UPPER RIDGE EXTENDS NNE ALONG 22N108W TO 
BEYOND 32N102W WITH THIS SHORTWAVE RIDGE AMPLIFYING NE AND 
MERGING WITH A NE TO SW LONGWAVE RIDGE THAT DOMINATES EASTERN N 
AMERICA. UPPER DIFFLUENCE UNDER THE RIDGE IS ENHANCING 
CONVECTION ALONG A COUPLE OF INVERTED LOW LEVEL TROUGHS EMBEDDED 
IN THE ITCZ. ONE TROUGH IS NEAR 136W AND THE OTHER NEAR 117W. 
THE UPPER DEBRIS MOISTURE FROM THESE CONVECTIVE AREAS SPREADS N 
ALONG THE RIDGE AXIS BECOMING A 480 NM WIDE MOISTURE PLUME 
CENTERED ALONG 14N119W TO BEYOND 32N102W. 

E OF THE LONGWAVE RIDGE OVER EASTERN N AMERICA A SHARP POSITIVE 
TILT UPPER TROUGH IS NOW SHIFTING E ACROSS THE W ATLC. A 
SHORTWAVE TROUGH EXTENDS SW INTO THE DISCUSSION AREA FROM 32N78W 
TO 17N90W THEN THROUGH A SMALL UPPER CYCLONE NEAR 7N102W AND 
CONTINUING S TO ANOTHER CYCLONE STATIONARY OVER THE EQUATOR AT 
100W. DRY UPPER AIR IS INDICATED ON MOISTURE CHANNEL ROUGHLY 
WITHIN 420 NM EITHER SIDE OF LINE 32N78W 1N108W.

AN ILL-DEFINED UPPER ANTICYCLONE IS NOTED OVER VENEZUELA NEAR 
7N62W. THE ASSOCIATED RIDGE CRESTS ALONG POINTS 10N92W 20N71W.
UPPER DIFFLUENCE UNDER THE RIDGE IS ENHANCING SMALL CONVECTIVE 
BURSTS ALONG THE ITCZ E OF 102W. DEBRIS MOISTURE IS ADVECTED NE 
ACROSS CENTRAL AMERICA AND ACROSS THE CENTRAL CARIBBEAN.

AT THE SURFACE...COLD FRONT ENTERS THE REGION THROUGH 30N129W 
AND EXTENDS SW TO BEYOND THE REGION NEAR 24N140W. HIGH PRESSURE 
OF 1017 MB IS ANALYZED NEAR 26.5N121W. HIGH PRESSURE COVERS THE 
AREA NORTH OF 18N WEST OF 118W.

GAP WINDS...GULF OF TEHUANTEPEC...MODEL GUIDANCE IS UP AND DOWN
WITH THE N-NE WINDS OF 20-25 KT THROUGH WED NIGHT THEN HIGH PRES 
OVER THE SE CONUS BUILDS SOUTH AND STRENGTHENS ALLOWING FOR
A SURGE OF STRONG NE WINDS TO PUSH THROUGH THE GAP AT GALE FORCE 
BEGINNING NEAR 1200 UTC THU.  NE WINDS OF 20-25 KT WILL CONTINUE 
ACROSS THE GULF OF PAPAGAYO FOR THE NEXT 36 HOURS THEN DECREASE.

$$
AGUIRRE